The present invention relates to remotely controlled, self-propelled lawn mowers. More particularly, it relates to remotely controlled, four wheel, self-propelled lawn mowers that use a belt and pulley system for steering control and electric power to propel the mower.
The history of remotely controlled lawn mowers from sheep to preprogrammed robots is replete with devices and techniques for easing the onerous lawn cutting task. Each inventor has faced the two basic elements of the problem, directional control and propulsive power, with varying degrees of success. It is known, for example, to use multiple gears to control forward, reverse, left and right motions. Such devices, however, may be difficult to produce due to the strict manufacturing tolerances and, importantly for the consumer, may be prone to failure and difficult to repair. (See U.S. Pat. No. 4,318,266 to Taube and U.S. Pat. No. 3,800,902 to Keller).
While other steering techniques using a belt and pulleys are generally known in remote control vehicles, these techniques have not been successfully applied to lawn mowers, probably due to the inefficiency or complexity of their arrangement or to their inability to adapt to the demanding mechanical stresses of a lawn mower. (See, for example, U.S. Pat. No. 3,095,937 to Vulliet-Durand).
While it is known to use direct current electric motors to propel a remotely controlled lawn mower, the position of the steering wheels in such mowers is fixed relative to the frame of the mower. Maneuvering a mower with fixed steering wheels may tend to tear up the lawn being mowed and may tend to unacceptably reduce mower speed when one wheel is slowed to turn the mower. See, for example, U.S. Pat. No. 3,789,939 to Geislinger.
It is accordingly an object of the present invention to provide a novel remotely controlled lawn mower that obviates the problems of the prior art and that is easy to use and that may be produced from relatively simple and low cost parts.
It is a further object of the present invention to provide a novel remotely controlled lawn mower that uses a simple and compact belt and pulley steering mechanism.
It is yet a further object of the present invention to provide a novel remotely controlled lawn mower that uses a battery to rotate a first set of drive wheels that are fixed in relation to the mower frame and to movably position a second set of steering wheels relative to the frame.
It is another object of the present invention to provide a novel remotely controlled lawn mower that prevents the mower from losing four-point contact with uneven terrain.
It is still another object of the present invention to provide a novel remotely controlled lawn mower that has wheel adjustments for setting lawn mowing height.
These and many other objects and advantages will be readily apparent to one skilled in the art to which the invention pertains from a perusal of the claims, the appended drawings, and the following detailed description of preferred embodiments.